C# 6.0：nameof操作符

class Program
{
    static void Main(string[] args)
    {
        WriteLine(nameof(Student));
        WriteLine(nameof(Student.Roll));
        WriteLine(nameof(Student.Name));
        WriteLine(nameof(Student.Address));
    }
}

class Student
{
    public int Roll { get; set; }
    public string Name { get; set; }
    public Address Address { get; set; }
}    

public string UserName
{
    get
    {
        return _userName;
    }
set
    {
        this.OnPropertyChanged("UserName");
    }
}    

public string UserName
{
    get
    {
        return _userName;
    }
    set
    {
        this.OnPropertyChanged(nameof(UserName));
    }
}